错误代码:1054.未知列

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问题描述

我有以下SQL语句:

SELECT efforts.user_id, project_tasks.task_name, sum(hours) 
FROM efforts, users, project_tasks
INNER JOIN PROJECT_TASKS pu ON efforts.project_task_id = pu.id  
INNER JOIN USERS u ON efforts.users_id = u.id
WHERE project_tasks.project_id = '2';

当我运行它时，出现以下错误:

And when I run it I get the following error:

Error Code: 1054. Unknown column 'efforts.project_task_id' in 'on clause'

为什么会出现此错误?

Project_task_id属于工作量表

Project_task_id belongs to efforts table

我的努力表的图片

已更新:

SELECT u.full_name, pu.task_name, hours 
FROM efforts
INNER JOIN project_tasks pu ON efforts.project_task_id = pu.id   
INNER JOIN users u ON efforts.user_id = u.id 
GROUP BY user_id, task_name

推荐答案

您的语法错误，应该是:

Your syntax is wrong, it should be:

SELECT efforts.user_id, pu.task_name, sum(hours)  
FROM efforts
INNER JOIN PROJECT_TASKS pu ON efforts.project_task_id = pu.id   
INNER JOIN USERS u ON efforts.user_id = u.id 
WHERE pu.project_id = '2';

这篇关于错误代码:1054.未知列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！